ABS fault

[NeilF]

Hi,

I've recently developed an ABS fault. Three lights came on with three bongs, though I'm pretty sure one of them wasn't the HDC light, but the ABC, TC and handbrake lights (not the three amigos?). Switching the ignition on they all go out with the exception of the ABS light, which then goes off after reaching 5mph. It stays off under normal driving and braking, but step on the brakes over loose stuff, and three lights come on again.

I've searched the forums but didn't see anything relevant

The fact that the light goes out normally suggests that it is not hub bearings or sensors? What else might I look out for before going to the Main Stealer or investing in a Nanocom?

02 Disco II, TD5

[NeilF]

To update, the fault seems to have gone away. ABS light goes out with the others (not at 5mph). TC worked this evening, going over a kerb.........

I hate intermittent faults; never there when you try to track them down only to reappear at inconvenient moments.

[sierrafery]

read the fault codes when u have the chance(not at steales off course)... the stored codes will put you in the right direction

100% sure that if u get "air gap too large... " code u must replace the hub there.... cos hub and SVS faults are intermittent... and the light actually goes off above 9 mph

[NeilF]

I'd like to read the fault codes, but I don't know how.

I have gone through the FAQ, searched the net on ABS fault codes, Blink test, Paperclip test, discovery ABS fault codes, you name it I've tried it - All I get is a circular route where posters just say 'Google discovery ABS codes/blink test/etc' but I never find the original instructions. I got the impression from some posts that Disco II's cant use the blink test anyway........

Must I buy a Nanocom or a ABS Amigo V1 USB : http://www.rswsolutions.com/index.php?option=com_content&view=article&id=56&Itemid=55

[sierrafery]

Nanocom or hawkeye...the ABS amigo doesnt worth that money for what it can do...u put a bit more but u'll have all the systems covered....blink test is just for D1 and RRC

[Snagger]

I believe the DII ABS system is the same Wabco system as used on the soft dash RRC. The brake warning light (the same one that the hand brake illuminates) is triggered by low reservoir levels or low accumulator pressure. The electric pump should fully charge the system within 45 seconds of energising. If it doesn't, the warning light will stay on, as will the ABS and ETC lights. A tired pump can still provide sufficient pressure, and letting the pump run for a few seconds before engine start (where the 45 time limit will be reset again) will give it more time to pressurise the system and cheat the time limit. Air in the accumulator or pump can also affect the pressurisation time. Replacement pumps cost about £800 new, so be systematic in your diagnosis! I recently did this on my RRC and replaced the pump with a second hand unit that has cured the issue.

A sensor problem can be down to wheel bearings or worn swivel bearings, but can also be due to worn CV joints, stub axle bushes and drive flanges. I had a faulty sensor which set of the ABS light on full lock, which transpires to be a break in the wire near the sensor head. A bad sensor can be cheaply diagnosed if identified on diagnostic computers by clearing the ECU fault memory and swapping the sensors in the affected axle from side to side and testing again after a drive that illuminates the light - if the ECU fault reports the other side from before, you know you have a bad sensor, but if the fault stays at the same wheel, you know it's a wheel, drive or swivel bearing fault.

[NeilF]

Thank you very much and I'll bear that in mind. I have a Hawkeye on order so hopefully, something will be revealed